Progressive pulmonary disease associated with chronic bacterial infection and airway inflammation is the major cause of morbidity and mortality in cystic fibrosis (CF) patients. CF lung disease may be characterized by chronic bacterial infection, with prevalence of infection increasing with age. CF patients with the most common CF transmembrane conductance regulator (CFTR) mutation, ΔF508, a deletion of a phenylalanine at position F508 of CFTR, often have markedly different clinical courses; some have less aggressive lung disease and survive into their 50s, while others have a precipitous decline in lung function and die of respiratory failure in their early 20s. What accounts for this phenotypic heterogeneity is unclear.
Early assessment of lung disease severity may present the best opportunity for treatment intervention. With the development of genetic testing, it is possible to identify genetic markers that will be indicative of a propensity to develop disease or indicative of a disease state. There remains a need to identify one or more genetic markers that are associated with lung disease in CF patients. These genetic markers may represent allelic variants, which may be useful in diagnosing lung disease severity, and whose products may be targeted for early intervention therapy.